Crop Pest Update

Summary

Insects: Grasshopper nymphs are being managed in some areas; some of these being field edge treatments. Alfalfa weevil is a concern in some alfalfa fields in the Eastern, Interlake and Central regions. Some have cut their alfalfa early as a means of managing the alfalfa weevil, others have used insecticides. Barley thrips are being noted in some barley fields, a field in the southwest was at boarderline threshold. Aphids are present in cereals in the Central and Eastern regions, but not at threshold levels. People are noting a lot of blister beetles in some crops; some of the species that seem to be abundant have larval stages that specialize in feeding on grasshopper eggs. Cereal leaf beetle feeding has been noted on some wheat and oat fields in the Eastern region; samples have been collected to determine the percent that are parasitized.

Diseases: The disease issues for the week have been, in order of reporting prevalence – 1. Bacterial blight in oats, 2. White heads in fall rye (primarily hybrid type) caused by numerous environmental stresses, not insect or pathogen, and 3. Lower canopy lesions in field peas (bacterial or fungal?).

Weeds: Spraying continues across the province, as some crops were reseeded we’ve got a big range in growth stages. Cereals are pretty much wrapped up, canola and soybeans have mostly had their first spray and second sprays are ongoing. Earliest fields were sprayed weeks ago, keep up with post –spray scouting so we can see which weeds have been missed or have started to regrow. Some products give good in-crop burnoff of bigger weeds or perennials but later the weeds start to regrow. If this is a problem in your fields then evaluate your herbicide choices, a different product might be better for next year. Plan your pre-harvest and post-harvest sprays to take care of these weeds that got missed. When doing a second spray in canola or soybeans leave at least 10 days between applications to let the crops recover. Watch crop staging to make sure you’re still within the maximum growth stage for crop safety and pre-harvest intervals.